Laparoscopy dates back to the turn of the 20th Century. Early laparoscopic techniques were used primarily for diagnostic purposes to view the internal organs without the necessity of conventional surgery. Since the 1930s, laparoscopy has been used for sterilization and, more recently, for suturing of hernias. U.S. Pat. Nos. 4,919,152 and 4,944,443 are concerned with techniques for suturing hernias. Another recent innovation is the use of laparoscopic surgery for removing the gallbladder.
U.S. patent application Ser. No. 07/706,781, the application of which this application is a Continuation-in-Part and which is incorporated herein by reference, describes an apparatus and method wherein the abdominal wall is lifted away from the underlying abdominal organs by an inflatable device which is introduced laparoscopically and, once in place, inflated to engage and lift an extensive area of the abdominal wall.
Even when such lifting techniques are used, it is still necessary to retract other organs to gain access to the organ or tissue to be treated or observed. In other procedures, to gain access to the organ or tissue to be treated or observed, it is necessary to separate the organ to be treated from tissue surrounding it. For example, to be able to observe the outer surface the heart, the outer surface of the heart has to be separated from the pericardium. To obtain the necessary retraction, current laparoscopic procedures use several small retractors inserted though plural incisions. Because such retractors have a relatively small surface area, they tend to damage and/or cause trauma to the retracted organs or tissue. Moreover, the requirement for plural incisions to heal may delay the patient's recovery.
One of the inventors of the present invention has used a modified Foley catheter to retract organs and tissue with less damage. The modified Foley catheter comprises a small, substantially spherical balloon on the end of a catheter which is inserted through a small incision into the body. After insertion, the balloon is inflated. The modified Foley catheter is used in a similar manner to a conventional retractor, but the retracted organ or tissue is contacted by the relatively large surface area of the balloon. Such a retractor reduces damage to retracted organs or tissues, but is inconvenient to use because it has to be kept in place by means of an external clamping arrangement, and its relatively large inflated balloon tends to obstruct access to the site to be treated.
U.S. patent application Ser. No. 07/794,590, of which this application is a Continuation-in-Part (the "parent application") and which is also incorporated herein by reference, discloses a number of different inflatable retraction devices for retracting an organ or a tissue (an "organ") to provide access to an organ or a tissue (a "tissue"). The inflatable retraction devices disclosed in the parent application are multi-chambered. An inflatable retraction device is packaged in a collapsed and compacted state, and is laparoscopically placed adjacent to the organ to be retracted. The large, main chamber of the inflatable retraction device is then inflated to expand the main chamber, which retracts the organ. Expanding the inflatable retraction device not only retracts the organ, but also causes the expanded main chamber to obstruct access to the tissue.
Once the main chamber of the inflatable retraction device is fully expanded, a second inflatable chamber is inflated. The second chamber, although normally providing less of a retraction force than the main chamber, provides sufficient retraction force to maintain the organ in its retracted state after the inflation pressure in the main chamber is released. Then, apertures are cut in the envelope of the main chamber to provide access to the tissue to be treated. The tissue is treated using instruments passed through the main chamber.
Experience with performing a variety of different procedures using the inflatable retraction devices disclosed in the parent application has indicated a number of desirable performance improvements, including: increasing the retraction force exerted by the second chamber; increasing the resistance of the both inflatable chambers to accidental deflation; increasing the ease of expanding the main chamber from its collapsed and compacted state; reducing the bulk of the inflatable retraction device in its collapsed and compacted state; and eliminating the need to cut apertures in the envelope of the main chamber to provide access to treat the tissue. One aspect of the invention in the parent application involved cutting an aperture in the envelope of the main chamber using a sharp object near the organ retracted by the inflatable retraction device.
The parent application also describes using the two-chambered inflatable retraction device for properitoneal hernia repair. A hernia is the protrusion of part of a body pan or structure through a defect in the wall of a surrounding structure. Most commonly, a hernia is the protrusion of part of abdominal contents, including bowel, through a tear or weakness in the abdominal wall, or through the inguinal canal into the scrotum.
An abdominal hernia is normally repaired by suturing or stapling a mesh patch over the site of the tear or weakness. The anatomical weakness of the hernia can be approached from inside or outside the abdomen. If approached intra-abdominally, the mesh patch, which has a rough surface, can irritate the bowel and cause adhesions. It is therefore preferred to install the patch properitoneally, in which the mesh patch is attached to the properitoneal fascia of the abdominal wall, and covered by the peritoneum. To attach the mesh patch to the properitoneal fascia, the peritoneum must be dissected from the properitoneal fascia.
The use of laparoscopic techniques to perform hernia repair is becoming increasingly common. In the conventional procedure for carrying out a hernia repair laparoscopically, an endoscope and instruments are introduced into the belly through one or more incisions in the abdominal wall, and are advanced through the belly to the site of the hernia. Then, working from inside the belly, a long incision is made in the peritoneum covering the site of the hernia. A small part of the peritoneum is dissected from the properitoneal fat layer to provide access to the fat layer. This is conventionally done by blunt dissection. In this procedure, it is difficult to dissect the peritoneum cleanly since patchy layers of properitoneal fat tend to adhere to the peritoneum.
In an alternative known extraperitoneal laparoscopic hernia repair procedure, an incision is made in the abdominal wall close to the site of the hernia. The incision is made through the abdominal wall as far as the properitoneal fat layer. The peritoneum is then blunt dissected from the properitoneal fat layer by passing a finger or a rigid probe through the incision and sweeping the finger or rigid probe under the peritoneum. After the peritoneum is dissected from the properitoneal fat layer, the space between the peritoneum and the properitoneal fat layer is insufflated to provide a working space in which to apply the mesh patch to the properitoneal fascia. During the blunt dissection process, it is easy to puncture through the peritoneum, which can be quite thin. A puncture destroys the ability of the space between the peritoneum and the fascia to hold gas insufflation. Also, it is difficult to dissect the peritoneum cleanly since patchy layers of properitoneal fat tend to adhere to the peritoneum.
The laparoscopic hernia repair technique described in the parent application enables a mesh patch to be attached to the properitoneal fascia without breaching the peritoneum. An incision is made through the abdominal wall as far as the properitoneal fat layer. An inflatable retraction device of the type described above is pushed through the incision into contact with the peritoneum, and is used to nudge the peritoneum from the underlying layers. The main chamber of the inflatable retraction device is then inflated to expand the inflatable retraction device towards the site of the hernia. As it expands, the inflatable retraction device gently dissects the peritoneum from the underlying layers.
Once the main chamber of the inflatable retraction device is fully expanded, the second chamber is inflated. The second chamber enables the inflatable retraction device to continue to maintain separation of the peritoneum from the overlying layers after the inflation pressure in the main chamber has been released.
One or more apertures are then cut in the envelope of the main chamber to provide access to the site of the hernia for instruments passed into the main chamber. With such an arrangement, instruments pass to the site of the hernia through the main chamber situated between the peritoneum and the overlying layers. In this way, a mesh patch can be attached to the properitoneal fascia without breaching the peritoneum.
Experience with this hernia repair technique has shown that the desirable improvements to the inflatable retraction device set forth above are also desirable when the inflatable retraction device is used to perform hernia repair. In addition, a number of additional improvements specific to inflatable retraction devices used for hernia repair have been identified, including: using a single inflatable retraction device usable to treat both sides of a bilateral hernia; providing an ability for the surgeon to locate the inflatable retraction device relative to the site of the hernia by feel when inserting the inflatable retraction device prior to expansion; and enabling the packaged inflatable retraction device to perform blunt dissection without the need to inflate the main chamber.
U.S. patent application Ser. No. 07/911,714, which is also a Continuation-in-Part of the parent application, and which is also incorporated herein by reference, discloses a properitoneal hernia repair technique which differs from the technique using the above-described two-chambered inflatable retraction device. The technique described in the '714 application uses a single-chambered inflatable retraction device to create a working space at the site of the hernia. The inflatable retraction device is removed and the working space is insufflated prior to treating the hernia.
A small incision is made at the umbilicus through the abdominal wall as far as the peritoneum. The single-chambered inflatable retraction device is introduced through the incision and is used to nudge the peritoneum away from the adjacent fat layer. The chamber is then partially inflated to expand the chamber, which dissects more of the peritoneum away from the adjacent fat layer. The chamber is then deflated and advanced towards the site of the hernia. The inflating and advancing process can be repeated to form a tunnel between the incision and the site of the hernia.
When the site of the hernia is reached, the chamber is fully expanded to create a working space at the site of the hernia. An endoscope can be inserted into the expanded chamber to obtain a visual confirmation of the hernia defect. The inflatable retraction device is then withdrawn from the working space, and a trocar tube anchored by a small balloon is inserted into the incision. Insufflation gas is passed through the trocar tube to insufflate the tunnel and the working space. The hernia is then treated using instruments passed into the insufflated working space through the insufflated tunnel.
Experience with using the single-chambered balloon technique just described has shown that the peritoneum can sometimes rise up and obstruct access to the site of the hernia. This occurs if the peritoneum is breached during the dissection process, and insufflation gas leaks into the abdominal cavity. This equalizes the pressure across the peritoneum, and the insufflation pressure no longer depresses the peritoneum away from the site of the hernia. It has also been found that blood accumulates in the tunnel leading to the site of the hernia, and contaminates the lens of the endoscope when the endoscope is passed through the tunnel. The endoscope must then be withdrawn from the tunnel, its lens cleaned, and another attempt to insert the endoscope made.